title: Mid-term results of self-testing of the international normalized ratio in adults with a mechanical heart valve.
abstract: BACKGROUND
  Commonly the frequency of international normalized ratio (INR) monitoring with a conventional laboratory test in stable patients is once a month. When using a dedicated personal device for INR assessment, the frequency may be increased to two or more times a month.
  
  
  OBJECTIVE
  To show that INR assessed by self-measurement at home is reliable and feasible in the mid-term and improves medical care.
  
  
  METHODS
  All patients in the study on INR self-measurement (clinical trial.gov: NCT00925197), conducted between 2004 and 2007, were re-contacted for mid-term follow-up. One hundred and seventy eight out of 192 patients who participated in the study answered a questionnaire. The average follow-up time was 4.2 years (±1) for the self-measurement group and 4.9 years (±1) for the laboratory-analyzed control group.
  
  
  RESULTS
  Only 26 patients (group A) continued to use INR self-measurement to monitor treatment with vitamin K antagonists (VKA). The main reasons to stop INR self-measurement were its high cost and difficulty in obtaining strips. There were significantly fewer bleeding complications (p=0.04) and complications related to VKA (p=0.01) in self-measured patients compared to the control group. Feelings of security and quality of life were also significantly better (p=0.002) for self-measured patients.
  
  
  CONCLUSIONS
  Many patients with a mechanical heart valve, who self-measured INR, continue to use this method for their follow-up because of its positive effects on their health and quality of life.
authors.affiliation: Heart surgery Department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France. Electronic address: kazarnoush@chu-clermontferrand.fr.
authors.forename: Kasra
authors.initials: K
authors.lastname: Azarnoush
authors.affiliation: Heart surgery Department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Enrica
authors.initials: E
authors.lastname: Dorigo
authors.affiliation: Bio-statistics unit, Délégation Recherche Clinique & Innovation, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Pereira
authors.affiliation: Cardiology department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Dauphin
authors.affiliation: Heart surgery Department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Geoffroy
authors.affiliation: Heart surgery Department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Dauphin
authors.affiliation: Heart surgery Department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Nicola
authors.initials: N
authors.lastname: D'Ostrevy
authors.affiliation: Heart surgery Department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Legault
authors.affiliation: Heart surgery Department, G. Montpied Hospital, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Lionel
authors.initials: L
authors.lastname: Camilleri
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000009:adverse effects; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D019934:International Normalized Ratio / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D012648:Self Care / Q000295:instrumentation*; D013923:Thromboembolism / Q000188:drug therapy; D014812:Vitamin K / Q000037:antagonists & inhibitors*
chemical_list: D000925:Anticoagulants; D014812:Vitamin K